Telephone signal apparatus



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' G. H. BLISS.

Telephone Signal Apparatus. No. 241.914. Patented May 24,1881.

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G. H. 'BLIS S. TelephoneSignal Apparatus.

I J a 1 WITNEEEE- U ITED STAT S PATENT OFFICE.

GEORGE H. BLISS, OF PITTSFIELD, MASSACHUSETTS.

TELEPHONE SIGNAL APPARATUS.

SPECIFICATION forming part of Letters Patent No. 241,914, dated May 24, 1881. Application filed November 29, 1880. (Model.)

T 0 all whom it may concern Be it known that I, GEO. H. BLISS, of Pitts field, county of Berkshire, and State of Massa chusetts, have invented a new and useful Improvement in Telephone Signal Apparatus, of which the followin g description, in connection with the accompanyingdrawings, is a specification. 7

My invention relates to telephone-signals, and is intended as an improvement in the signal invented by me for which Letters Patent No. 223,469, dated January 13, 1880, and No. 225,327, March 9, 1880, were. granted, to which reference may be had. In the said applications a series of clock-works were described as arranged to run synchronously, and each controls a signal-bellin the circuit, allowing it to sound only at a certain predetermined period of time, the said period being different at each instrument, so thatonly one bellcan be sounded at a time, and the periods recur at regular int.ervalsas, for example, once a minute. In the latter of the said patents the bell-hammer is mechanically heldinoperative and the coils of its magnet shuntcd,-except at the period devoted to that'particular instrument for operating its signal. There was also shown in the said patents an automatic stop mechanism to stop all the clock-works when they arrived at a definite point, the said stop remaining in position for a short interval, during which any slowrunning clocks would catch up and be stopped, so that when allowed to start again by the disengagement of the stop all the said clocks would be in exact unison.

In the present embodiment of my invention the clocks are all automatically stopped at the end of the interval in which each has had its individual period for operation, and they remain so stopped until it is desired to signal one of the stations again, when theinstruments are all started again sim ultaneously by electromagnets removing the stop from engagement with the clock-work.

The electro-magnets for starting the clockworks, and which may be called the starting magnets, are independent of those that operate the signals; and the invention consists, partly, in the combination, with the clockworks and starting-magnets, of switches automatically operated by the said clock-works to close a shunt around the said starting-magnets immediately after the said clock-works have started, and to keep the said shunt closed during the entire interval in which the period for signaling at each instrument occurs, thereby removing the resistance of the said starting-magnets from the circuit when used for signaling, the said switches breaking the shunts just before or at the moment that the clockworks are stopped, so that thereafter any current will be compelled to pass through the said magnets.

That portion of thedevices and circuits which is operatively connected with the starting apparatus will be hereinafter distinguished by the word starting from that portion connect ed with the signaling apparatus proper, which will be qualified by the word signaling or signal.

The signals, which may be operated by magneto-electric currents in the usual manner, are placed in the main circuit, and shunt-circuits are provided, which cut out the said magnets, the said shunt-circuits being controlled by the clock-works, to thereby control the operation of the signals. In my present invention circhit-breakers are placed in these shun t-eircuits, and are operated by cams placed preferably on an arbor that makes one complete revolution in the interval that the clock-work is running, between the moment that it is started and that at which it is automatically stopped. This arbor may be called the main arbor, and also operates the mechanism by which the clock-work is stopped. The cams for breaking the shunts are placed at different angular positions on the said main shaft in the different instruments, each being of proper shape to retain the shunt broken during a certain period in which the signal at that station may be sounded, after which the cam disengages the said circuit-closer, allowing itto close the shunt, and the controlling-cam in another instrument opens its shunt and retains it open for a certain period, during which any electric currents that may be thrown upon the circuit will have to pass through the signal-operating magnet and cause it to sound the signal.

In the central-office instrument, and in the others if desired, a pointer is placed on the main shaft and rotates therewith over a dial,

which is divided to correspond with the cam surfaces in the different instruments, so that while the said pointer is passing through division 1 of the said dial the cam in the instrument of the first station is holding the short circuit open, all the others being closed, and while it is in division 2 the shunt at the second station is open, and so on. Thus the operator, by watching the pointer, will know at what time each signal can be sounded, and by throwing on or generating; electric currents at the proper time, as when the pointer is in a certain division, the currents will be caused to pass through and operate the signalingmagnet at the station corresponding to the said division, and it will be seen that only the resistance of the particular signaling-magnet in operation is interposed in the circuit at any one time, and that while the instruments are stopped all the signalinganagnets are shortcircnited, as there are no signal-shunts open in this position of the main arbor.

The invention further consists in details of construction and combination of the mechanical portions ofthe apparatus, as will be hereinafter fully described.

Figure 1 is a front view of a signal apparatus embodying my invention, the parts being in their normal position with the clockwork stopped, and the front portion of the inclosing-case and the dial being removed; Fig. 2, a detail of the main shaft and mechanism co-operatin g therewith in the position assumed shortly after the period of operation of the signal has begun; Fig. 3, a front view of the dial and pointer of the instrument in the same position as in Fig. 2; Fig. 4, a side elevation of a portion of the clock-work shown in Figs. 1 and 2, and Fig. 5 a diagram showing the arrangementof circuits and the relation of the signal-cams on the main shaft in a series of signals.

The clock-works are shown as driven by a mainspring, a, connected with and actuating a train of wheel-work, b b 0 &c., which may be and is shown as the same as that of an ordinary clock, and terminates in an escapement, shown as governed by a balance, 0, on a shaft, (1, to regulate the movement of the train in the usual manner, the rate being substantially uniform in all the instruments that are to control the signals of a given circuit.

The shaft 0 of the wheel I) has upon it the main cams which control the stoppingmechanism of the clock, as well as the circuits by which the electric currents are made to pass through the starting and signaling magnets, or are shunted around the said magnets. This shaft preferably revolves in about a minute, as this interval is usually sufficient to allow a proper period for the signaling of all the signals on a circuit, each in its turn, and is provided with a stop-controllin g disk, f, which operates on a projection, 2, of the stop-lever g, pivoted at 3, and adapted, when in the proper position, (see dotted lines, Fig. 3,) to engage the stop-cam II on the balance-shaft d, and

thereby arrest the movement of the clock-work. The specific construction of this stopping mechanism is not herein broadly claimed, as it will form the subject of a future application.

In order to operate the stop-lever g to stop the clock-work, its controlling-disk f is provided with anotch, 4, to receive the projection 2 of the said lever, and allow it to turn on its pivot and fall into engagement with the stopcani h, the said notch and cam being so placed with relation to the time of movement of their respective shafts that the lever is allowed to turn just when the balance is completing its oscillation in the direction of the arrow, and falls against the shoulder 5 of the cam h and stops the train when the full force of the hairspring is acting 011 the balance, so that the moment the stop-lever is disengaged therefrom the balance beginsits-oscillation and the train starts with certainty. The lever is disengaged from the cam h to thus allow the train to start by an electro-magnet, i, the armature of which is provided with a long finger, j, the end whereof passes in front of an arm, k, extended from the lever 9, so that when the said starting-magnet attracts its armature the fingerj thereof strikes the arm k and tilts the lever g, disengaging it from the cam 71, and at the same time raising the projection 2 from the notch 4. The rear face of the notch 4 is inclined, as shown, and in a single oscillation of the balance 0 the disk fis moved so far that the said inclined side of the notch 4, in engaging the projection 2, will hold the lever disengaged from the shoulder 5 of the cam it, so that a single momentary impulse is sullieient to cause the clock-work to start, after which the controlling-disk f, or the rear side of the notch thereof, will prevent the stop-lever from again stopping the train until the notch comes around again in the rotation of the disk f.

The armature of the magnet t has a retraotor consisting of a fine spring-wire, 1, bearing laterally against the tingerj.

The main-line circuit, in which all the signals are situated, is connected where it enters the station with the binding-screw 10, whence it passes by wire 15 to the magnet i, from the coils of which the circuit is continued by wire 16 to the binding-screw 11, whence it passes through the signal-operatin g mechanism to be hereinafter described, and thence to the hinding-screw 10 of the signal-controlling mechanism, such as shown in Fig. 1, at the next station, or, if atthe last station, itpasses to ground to complete the circuit.

Branch wires 17 18, connected with the wires 15 16, respectively on either side of the coils of the magnet i, are joined the former to the pin on and the latter to .the spring a, both supported on a block,o, of insulating material,the said spring pressing against the said pin and forming electrical contact therewith, except when positively raised therefrom by the liftin g-toe p on the main arbor c. The said too 1) is so placed relative to the notch 401' the stopcontrolling disk fin all the instruments that it raises the spring a from the pin m just before the trains are stopped by the lever g, and retains it thus raised and the branch or shunt circuit between the wires 17 18 broken until just after the trains are started, when the toe p at once passes the end of the spring a and allows it to fall into contact with the pin m. By this arrangement, when the clocks are stopped all the electric currents passing over the main circuit between the screws 10 11 are obliged to pass through the magnets i, to thus cause the said magnets to attract their armatures and start the train, as before described; but after the said trains are started the shuntcircuits through the wires 17 18 are closed, thereby cutting out the resistance of the magnets 2', which'thus does not have to be overcome by the currents which operate the signals proper.

The signal-bells, which may be of any usual construction, are shown at s in Fig. 5 as of the well-known kind, containing alight polarized armature adapted to be vibrated under the action of the rapidly-reversed currents generated by an ordinary magneto-electric machine; but it is obvious that the said signals might be either single-tap bells or vibrators, or the operating-magnets shown might be merely relays to close a local signal-operating circuit. In either case the electro-magnet 1, operating or directly controlling the signal .9, is placed in the main circuit between the starting-magnet of one controlling-instrument and that of the next, as shown in Fig. 5, and branch wires 21 22 pass from either side of the said signalmagnet r to the binding-screws 12 13 of the controlling-instrument, where the said branch wires 21 22 are continued by wires 23 24: to the pin it and spring u, forming a second circuitbreaker similar to the one at it previously described, and mounted beside it on the same insulating-block 0. This circuit-breaker normall; remains closed, thus completing the branch or shunt circuit 21 22 23 24 around the signal-magnets 1", (see Fig. 5,) sothat owing to the greater resistance of the said magnets the greater portion of the currents pass through the said shunts, and the signals are consequently not operated by the currents which operate the starting-magnets to start the trains, nor by any currents, except when the said branch or shunt is broken, which never takes place in but one at a time, owing to the difference in position of the cams c. When the trains are thus started the circuit-breakers ta in the different controlling instruments are each opened, one-after the other, by the signal-controlling cams v on the main arbors e, andthese cams are properly shaped to retain the said circuit-breakers open for a suflicient period to allow the corresponding signal to be operated.

In Fig. 5 the signaling-cams o and circuitbreaker t u are'shown separately from the toes p and circuit-breakers m a for the sake of additional clearness, the shaft 6 being indicated twice at each instrument, and the circuits and magnets are shown in full at two of the stations, while at the rest of the stations only the circuit-breakers t u and their operating-cams o are shown, as all the other parts are the same at all the stations.

It will be seen that the camso are so placed on the main arbors 0 relative to the stopping and starting point of the said arbors governed by the notched controlling-disks that when the said arbors are all started simultaneously and rotate isochronously first one engages the end of the corresponding spring and raises it from engagement with the pin t, breaking the shunt around and causing the circuit to pass only through the corresponding si gnal-ma gnet r,and then when the said cam has passed the spring u, and allowed it to drop and close the said shunt, the cam at the uextinstrument engages its spring a, and after it has passed the one at the next instrument operates similarly, and so on for as many stations as there may be, a certain portion of theisochronous rotation of the said main arbors being devoted to the operation of each cam o, and no two of them operating at the same time to open their respective shunts.

The main arbors e are provided with pointers to, (see Fig. 3,) which, as the said arbors rotate, pass over a dial, as, which is divided into spaces marked 1 2 3, &c., which correspond to the position of the cams n at the different stations, so that while the said pointer is passing through the space marked 1 the cam 12 at station 1 is holding the circuit-breaker t a open, and while passing through the space2 the circuit-breaker t u at station 2 is open, and so on.

At the right hand of Fig. 1 a starting-arm, y, is shown pivoted at 7, and provided with a flexible finger, S, which, as the said arm is rocked on its pivot by the operator depressing the end thereof which extends out through the case, comes in engagement with the side of the balance 0 and sets it into oscillation, the function of the said arm being merely to start the clock when it is stopped with the balance in a middle position of its oscillation, as when the clock is run down.

The operation is as follows: The instruments are normally all stopped, as indicated in Figs. 1 and 5, the levers g engaging the shoulders 5 of the stop-cams h and the toes 2 holding the springs n disconnected from the pins m. The cams 'v are then at different distances from the ends of the springs a and the pointers to are at the zero-point, or vertical. Supposing, for example, it is desired to signal station 4, the operator sends a current over the circuit, which passes through all the starting-magnets i and causes them to attract their armatures, and by the connected fingers j to throw the levers 9 off from the shoulders 5 of the cams it, allowin g all the clock-works to start simultaneously. As the pointer to passes through the space 1 the signaling-shunt 21 22 23 24 at the first station is broken by the cam o engaging the spring a, and as the said pointer passes to space 2 the signaling-shunt at station 1 is closed and at station 2 is broken, and a similar operation takes place as the pointer passes into the spaces 3 and 4. While the pointer is passing through space 4, and the signal-shunt at station 4 is consequently broken, the operator sends to line electric currents of the proper kind to operate the signals 5, being in this instance the short reversed currents generated by a magneto-machine, and the said currents, in passing over the line, will follow the shunts 17 m n 18 around the starting-magnet i, the said shunts being closed when the clock-works first start, as hereinbetore described, and at all the stations except station 4 the said currents will also pass through the shunts 21 23 a 1524 22 about the signaling-magnets 2', which will consequently not be operated thereby; but at station 4 the currents will be obliged to pass through the coils of and operate the signalingmagnet 1', since the signaling-shunt is broken at this point by the cum 1*, as shown in Fig. 2.

The operator may continue to send the currents and operate the signal at station 4 as long as the pointer to is passing over the space 4 and the cam v at station 4 is holding up the spring a; but the moment that it arrives at the end of the said space the said currents must cease, as after this moment they would operate the signal at station 5 instead ofthat at station 4.

If desired, the disksf may be provided with two or more notches arranged at uniform intervals about its periphery, and the dials marked to correspond-as, for example, it there were only four stations on the circuit the said disk might have two notches 4 directly opposite one another, and the figures 5 6 7 S of the dial be replaced by the figures 1 2 3 4.

If desired, a second notch 4 might be placed close to the notch shown, so as to stop the pointer just before it arrives at the zero-point, such position of the pointer indicating that the line is not in use and when the subscribers have finished their communication the signals will be started again and immediately stop with the pointer at the zero-point, the projections 2 of the levers g then falling into the notch we have first described.

I claim- 1. In an individual signal apparatus, a series of instruments, each consisting of a clock-work adapted to control the operation of the corresponding signal, and an automatic stop mechanism to stop the said clock-work at a definite point, combined with a starting-magnet to operate the said stop mechanism and allow the clock-work to start simultaneously with those of the other instruments of the series, and a shunt or short circuit around the said starting-magnet and circuit-breaker therein, controlled by the said clock-work, whereby the said shunt-circuit is broken when the said clockwork is stopped and closed when the clockwork is in motion, substantially as and for the purpose described.

2. A clock-work having an oscillating balance and an inclosing-case therefor, combined with a starting-arm extended outside the said ease, and provided with a flexible finger or wiper to engage the said balance and set it in oscillation when it has stopped in an intermediate position in its oscillatory movement, substantially as described.

3. The combination of the notched controlling-disk, the stop-lever, and its projection controlled thereby, and the balance and balanceshat't of the time-train and stop-cam thereon, arranged and to operate substantially as described.

4. A series of signaling-instruments each consisting of a clock-work or time-train, the automatic stop mechanism therefor, and the starting and signaling magnets in a single circuit, combined with independentshunts around the said magnets and circuitclosers therein operated by the said clock-work, all arranged as described, whereby, when the clocks are stopped, the si gnal-magnet shunts are all closed and the currents confined to the starting-magnets, and when the clock-works are in motion the starting-magnet shunts are closed and the signal-magnet shunts in the different instruments are opened one at a time in succession, as and for the purpose set forth.

In testimony whereofI have signed my name to this specification in the presence of two subscribing witnesses.

GEORGE H. BLISS.

Witnesses THos. P. PINGREE, JOHN F. VAN DEUSEN. 

